1. Field of the Invention
This invention relates to a stabilizing assembly for a mining machine and more particularly for a stabilizing assembly mounted on the mining machine body portion in a manner to extend substantially the width of the conveyor support frame on the body portion to effectively anchor the rearward portion of the mining machine and thereby reduce the rocking motion of the mining machine during the mining operation.
2. Description of the Prior Art
Continuous mining machines, as illustrated in U.S. Pat. No. 3,774,969, are utilized in underground mining operations to continuously dislodge solid material from the face of a mine shaft. A boom member extends forwardly from an elongated body portion of the mining machine that is propelled through the mine on endless crawler tracks. The boom member is pivotally connected to the mining machine body portion and rotatably supports a cutter drum having peripherally extending elements. The cutter drum extends transversely to the longitudinal axis of the body portion, and upon rotation the cutting elements dislodge solid material from the mine face.
The dislodged material is moved rearwardly of the cutter drum by a gathering device onto the receiving end of a conveyor mechanism that extends longitudinally on the body portion of the mining machine. The conveyor mechanism includes a discharge end portion that is supported by the conveyor support frame for horizontal pivotal movement rearwardly of the mining machine. A main conveyor portion is pivotally connected to the conveyor support frame for vertical pivotal movement. The main conveyor portion is connected to the discharge end portion by suitable linkage mechanism to permit horizontal pivoting of the discharge end portion relative to the main conveyor portion. The discharge end portion is also vertically movable with the main conveyor portion.
With this arrangement the conveyor discharge end portion is operable to be maintained in material receiving relation with a material haulage vehicle or another conveyor as the mining machine maneuvers the cutter drum to dislodge the material from the mine face. By maintaining the discharge end portion in material receiving relation with the haulage vehicle, a continuous mining operation is carried out by the conveyance of the loose material from the mine face as the solid material is dislodged from the mine face. Thus during the mining operation the conveyor mechanism is being moved both vertically and horizontally and the cutter drum is moved by the boom member to perform upward and downward shear cuts in the mine face. Consequently, considerable forces are imparted to the mining machine body portion tending to displace or rock the body portion from its selected position for performing the shear cut in the mine face.
In order to stabilize the mining machine body portion as the boom member is raised and lowered to maneuver the cutter drum and dislodged material is being conveyed rearwardly on the body portion by the conveyor mechanism, it is known to rigidify or stabilize the body portion by anchoring the body portion on the mine floor. Anchoring the mining machine body portion is accomplished in one manner by pivoting a stabilizing arm member into engagement with the mine floor. The arm member is moved downwardly with sufficient force generally under the action of piston cylinder assemblies to sufficiently embed the arm member into the mine floor and thus provide an anchor for the mining machine body portion on the mine floor. U.S. Pat. No. 4,088,371 illustrates this general arrangement.
It is also known to use stabilizing devices with other types of machines that are operable in an underground mine. U.S. Pat. No. 3,865,197 discloses a mine roof drilling machine which is carried on a mobile body portion. During the drilling operation the mobile body portion is stabilized by an arm member which is pivotally connected to the frame of the body portion to move downwardly into engagement with the mine floor to rigidify the body portion and maintain it immovable during the drilling operations.
With the conventionally known stabilizing assemblies for continuous mining machine, the stabilizing assemblies are positioned beneath the conveyor support frame at the rearward end portion of the body portion. The piston cylinders for actuating the stabilizing assembly are also positioned beneath the conveyor support frame. One end of the piston cylinders is connected to the conveyor support frame and the opposite end or the extensible piston rod is connected to the stabilizing assembly. One end of the stabilizing assembly is, in turn, connected to the lower surface of the conveyor support frame.
One disadvantage with the known arrangement for connecting the piston cylinders to the stabilizing assembly is the positioning of the piston cylinders beneath the conveyor support frame and inboard of the lateral edges of the stabilizing assembly. Consequently, the stabilizing assembly must be constructed to permit the stabilizing assembly to pivot past the piston cylinders. As a result the pivotal connection of the piston cylinders to the conveyor support frame and the pivotal connection of the stabilizing assembly to the conveyor support frame are very close together. This provides for a reduced lever arm distance between the respective pivotal connections. Consequently, the force generated by the piston cylinders to both raise and lower the stabilizing assemblies is limited.
Therefore, there is need in a continuous mining machine for a stabilizing assembly that is pivotally connected to the body portion of the mining machine and actuated by piston cylinders in an arrangement to provide a maximum bearing surface in contact with the mine floor to securely anchor the mining machine and to generate the required force to efficiently move the stabilizing assembly into and out of its operative position.